JP5312499B2 - Mobile communication terminal and information display method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a portable communication terminal for providing more effective information on an azimuth to a user. <P>SOLUTION: The portable communication terminal performs clocking processing to clock the present time, acquires precision information showing whether a precision lowering region where precision of a detection value of a terrestrial magnetism sensor 158 is easily lowered is included in a region shown in a map displayed on a display section 155 at the present time from a prescribed information provider via a radio communication section 150, and displays the acquired precision information on the display section 155. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a mobile communication terminal such as a mobile phone provided with a geomagnetic sensor for measuring a geographical orientation and an information display method thereof.

  Conventionally, there has been a demand for a device that confirms the geographical position of the current location and guides the route to the destination by a map, and a car navigation device is known as a device that satisfies such a demand.

  In general, a car navigation device receives and processes signals (hereinafter referred to as GPS signals) transmitted from a plurality of GPS (global positioning system) satellites to determine the geographical position of the current location, and Map data is read from a database stored in a storage unit (DVD, hard disk, etc.) in the apparatus and displayed on a display. In addition, a vehicle movement trajectory is calculated using a vehicle speed sensor and a gyro sensor, and a map matching process is performed to detect the degree of coincidence between this and the road on the map, thereby correcting the positioning error.

  However, even when not in a car, there is a request to know where you are and how to get to your destination. doing.

  Initially, mobile phones with a navigation function did not have a device for measuring the direction, so a heading-up display commonly used in car navigation devices (a map with the direction of travel toward the top of the screen) It is difficult to display a map that is easy to understand for the user, such as a rotating display.

  Therefore, in recent years, a mobile phone with a navigation function has been proposed in which heading-up display is possible by measuring the direction using a geomagnetic sensor.

JP 2004-28837 A JP 2002-328042 A JP-A-10-197258

  However, in buildings, bridges, underground malls, etc. that use a lot of magnetic rebars and steel frames, trains, power stations, factories, etc. that use large currents, there is a strong magnetic field that hinders detection by geomagnetic sensors. Has occurred. Since there are many places in the city where such external magnetic fields are generated, when a pedestrian uses the navigation function of a mobile phone in a city, the direction accuracy is often lowered due to the influence of the external magnetic field. is there.

  On the other hand, in mobile phones, due to size and cost constraints, it is possible to correct azimuth measurement errors using a detection method other than a geomagnetic sensor, such as detection of a moving direction using a gyro sensor in a car navigation device. Have difficulty. Therefore, there is a disadvantage that the detection error of the geomagnetic sensor leads to a decrease in the accuracy of the azimuth as it is.

  This invention is made | formed in view of this situation, The objective is to provide the portable communication terminal which can give a user the information of a more effective azimuth | direction, and its information display method.

  A mobile communication terminal according to a first aspect of the present invention includes a wireless communication unit, a geomagnetic sensor that detects geomagnetism, a position information acquisition unit that acquires information related to the geographical position of the current location, a display unit, The display means calculates the geographical direction based on the detection value of the geomagnetic sensor, and displays the calculated direction information and the map around the current location specified based on the position information acquired by the position information acquisition means. A control unit for displaying the current time in a region indicated by the map displayed on the display unit. Accuracy information indicating whether or not an accuracy-decreased region where the accuracy of the detection value of the geomagnetic sensor is likely to be reduced is included from a predetermined information provider via the wireless communication means, and the obtained accuracy information The display on the display means.

  A mobile communication terminal according to a second aspect of the present invention includes a geomagnetic sensor that detects geomagnetism, a position information acquisition unit that acquires information related to the geographical position of the current location, a display unit, and a detection value of the geomagnetic sensor. Control means for calculating a geographical orientation based on the information and displaying the calculated orientation information and a map around the current location specified based on the position information acquired by the position information acquisition means on the display means And a storage means for storing information on the accuracy-decreasing area where the accuracy of the detection value of the geomagnetic sensor corresponding to the time is likely to be reduced, and the control means The time measurement process is performed, and accuracy information indicating whether or not the reduced accuracy area is included in the area indicated by the map displayed on the display means at the current time obtained by the time measurement process is displayed. To be displayed on the display means.

  Preferably, the control means may control the orientation of the map according to the azimuth information when displaying the azimuth information and the map on the display means.

  Preferably, the control unit may fix the map to a predetermined direction and display the map on the display unit when the current location specified based on the position information is included in the reduced accuracy area.

  Preferably, the control means may cause the display means to display information indicating whether or not the current location specified based on the position information is included in the reduced accuracy area.

  Preferably, when the detected value of the geomagnetic sensor is in a predetermined abnormal state when the information on the azimuth is displayed on the display unit, the control unit has the position information at a point where the abnormal state has occurred. The position information acquired by the acquisition unit may be transmitted to the predetermined information provider by the wireless communication unit.

  An information display method for a mobile communication terminal according to a third aspect of the present invention includes: a wireless communication unit; a geomagnetic sensor that detects geomagnetism; a location information acquisition unit that acquires information related to the geographical location of the current location; Display means for displaying geographical direction information calculated based on the detection value of the geomagnetic sensor and a map around the current location specified based on the position information acquired by the position information acquisition means; An information display method for a mobile communication terminal for displaying information on a mobile communication terminal, wherein the map displayed on the display means indicates the information on the azimuth and the map on the display means. The wireless communication means obtains accuracy information indicating whether or not the region includes an accuracy-decreasing region where the accuracy of the detection value of the geomagnetic sensor is likely to decrease at the current time from a predetermined information provider. Having a first step to get through, and a second step of the obtained accuracy information in the first step is displayed on the display means.

  An information display method of a mobile communication terminal according to a fourth aspect of the present invention includes a wireless communication unit, a geomagnetic sensor that detects geomagnetism, a position information acquisition unit that acquires information related to the geographical position of the current location, and Display means for displaying information on the geographical direction calculated based on the detection value of the geomagnetic sensor and a map around the current location specified based on the position information acquired by the position information acquisition means, and at the time And a storage means for storing information on the accuracy-decreased area where the accuracy of the detected value of the corresponding geomagnetic sensor is likely to be reduced, and the information display method of the mobile communication terminal for displaying information on the mobile communication terminal, A first step of measuring and whether or not the reduced accuracy region is included in the region indicated by the map displayed on the display means at the current time obtained by the first step The to accuracy information; and a second step of displaying on the display means.

  According to the present invention, more effective azimuth information including information related to azimuth accuracy can be given to the user.

It is a block diagram which shows the structural example of the system for acquiring the information of geographical location and map in the mobile telephone which concerns on embodiment of this invention. It is a conceptual diagram of the accuracy information map and correction information map which a navigation server apparatus has. It is a perspective view of the mobile phone in an open state. It is a perspective view from one side of a cellular phone in a closed state. It is a perspective view from the other side of a cellular phone in a closed state. It is a perspective view which shows the board | substrate mounting state in the inside of a board | substrate mounting housing | casing. It is a block diagram which shows the structural example of the mobile telephone which concerns on embodiment. It is the flowchart which illustrated an example of the GPS signal reception process. 3 is a flowchart illustrating an example of navigation processing according to the first embodiment. It is a figure which shows an example of the map information transmitted from a navigation server apparatus. 5 is a flowchart illustrating an example of display image rotation processing in a mobile phone. It is a figure for demonstrating the calculation method of an azimuth. It is the flowchart which illustrated an example of the azimuth | direction calculation process which concerns on 1st Embodiment. It is the 1st flowchart illustrating an example of the direction calculation processing concerning a 2nd embodiment. It is the 2nd flowchart which illustrated an example of the direction calculation processing concerning a 2nd embodiment. 10 is a flowchart illustrating an example of navigation processing according to a third embodiment. 10 is a flowchart illustrating an example of a geomagnetic detection value abnormality notification process executed in a mobile phone according to a fourth embodiment. It is a figure which shows an example of the update process of the precision information in the navigation server apparatus which concerns on 4th Embodiment.

  Hereinafter, four embodiments in the case where the present invention is applied to a multi-function mobile phone having a navigation function and an imaging function will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a block diagram illustrating a configuration example of a system for acquiring geographical position and map information in the mobile phone 100 according to the embodiment of the present invention.

The mobile phone 100 receives GPS signals transmitted from three or more GPS satellites 200 that go around a known orbit. Then, the received information on the GPS signal is transmitted from the base station 300 to the GPS server device 401 via the communication network, and the current location information is acquired from the GPS server device 401.
In addition, the mobile phone 100 transmits the location information of the current location acquired from the GPS server device 401 to the navigation server device 402 via the communication network from the base station 300, and information on the map around the current location and the geomagnetic detection value at the current location. Information (accuracy information) related to the accuracy of the current position and information (correction information) related to the correction of the azimuth at the current location are acquired from the navigation server device 402.

  The GPS server device 401 calculates the geographical position of the mobile phone 100 based on the information of the GPS signal transmitted from the mobile phone 100 via the communication network. Then, the calculated position information is transmitted from the communication network to the mobile phone 100 via the base station 300.

  The navigation server device 402 searches the database for map information around the mobile phone 100 based on the position information sent from the mobile phone 100 via the communication network. Then, the searched map information is transmitted from the communication network to the mobile phone 100 via the base station 300.

  The navigation server device 402 includes an accuracy information map MI1 and a correction information map MI2, which are databases in which the above-described accuracy information, correction information, and position information are mapped and mapped.

FIG. 2 is a conceptual diagram of the accuracy information map MI1 and the correction information map MI2 that the navigation server device 402 has. When the location information P of the current location is given from the mobile phone 100, the navigation server device 402 reads out the corresponding accuracy information I1 (P) and correction information I2 (P) from the accuracy information map MI1 and the correction information map MI2. The map information is transmitted to the mobile phone 100.
More detailed contents of the accuracy information and the correction information, and processing of the mobile phone 100 using them will be described later with reference to FIG. 9 and FIG.

3, 4, and 5 are diagrams illustrating an example of the appearance of the mobile phone 100.
3 is a perspective view of the mobile phone 100 in an open state, FIG. 4 is a perspective view from one side of the mobile phone 100 in a closed state, and FIG. 5 is a mobile phone in a closed state. 4 is a perspective view from the other side of the telephone 100. FIG.

As shown in the figure, in the mobile phone 100, a first casing (upper casing) 2 and a second casing (lower casing) 3 are openable and closable (movable) via a movable mechanism section 4. It is connected.
In addition, the movable mechanism part 4 is comprised so that two housings, the 1st housing | casing 2 and the 2nd housing | casing 3, can rotate relatively centering on the predetermined | prescribed rotating shaft.

As shown in FIGS. 3 and 4, the first housing 2 has, for example, an LCD (liquid crystal display) panel or the like on the first surface 2 a that is exposed regardless of the operating state (open state, closed state) of the movable mechanism unit 4. A display panel 21 including an organic EL (electroluminescent) display panel is disposed. A speaker 22 is built in the upper portion of the display panel 21 in FIG.
The display panel 21 is included in a display unit 155 described later. The speaker 22 is included in an audio processing unit 156 described later.

  The second housing 3 is configured by superimposing a substrate mounting housing 31 on which a substrate is mounted and a lid side housing 32 forming a lid of the substrate mounting housing 31.

A numeric keypad button 311a, a cursor button 311b, and an enter button 311c are provided on the outer flat surface 31a of the board mounting housing 31 of the second housing 3, that is, the surface 31a that faces one surface of the first housing 2 in the closed state. The operation key 311 is provided. A microphone 312 is built in the lower part of the operation key 311 in FIG.
The operation key 311 is included in a key input unit 154 described later. The microphone 312 is included in an audio processing unit 156 described later.

As shown in FIG. 5, the outer plane 32b exposed in the lid side casing 32 of the second casing 3 regardless of the open state and the closed state is closer to the side closer to the connecting portion of the movable mechanism portion 4 than the center portion. The optical system 34a of the camera module 34 is disposed.
In addition, on the outer plane 32a of the lid side housing 32 of the second housing 3, the flash light from the built-in flash lamp is radiated to the outside in parallel with the optical system 34a on the side closer to the coupling portion than the optical system 34a. A light emitting window 321 for emitting white light as a photographing assistance during close-up photography or the like is disposed.
The camera module 34 is included in an imaging unit 157 described later.

  As shown in FIGS. 3 and 4, a camera module tact switch 35 is disposed on one side of the second housing 3, and a connecting portion is provided on the other side of the second housing 3. A memory card slot 33 for inserting a memory card is formed on the near side.

FIG. 6 is a perspective view showing a substrate mounting state in the inside 31 b of the substrate mounting housing 31.
As shown in FIG. 6, the main board 37 is mounted in the interior 31 b of the board mounting housing 31 over the entire bottom surface.
A memory card unit 159 to which a removable memory card is mounted is mounted on the main board 37 at a position facing the memory card slot 33.
A geomagnetic sensor 158 is mounted at a position near the center of the main board 37 adjacent to the memory card unit 159.

FIG. 7 is a block diagram illustrating a configuration example of the mobile phone 100 according to the embodiment of the present invention.
A mobile phone 100 illustrated in FIG. 7 includes a wireless communication unit 150, a GPS signal reception unit 151, a storage unit 152, an open / close determination unit 153, a key input unit 154, a display unit 155, and a voice input / output unit 156. An imaging unit 157, a geomagnetic sensor 158, a memory card unit 159, and a control unit 160.
The wireless communication unit 150 is an embodiment of the wireless communication means of the present invention.
The GPS signal receiving unit 151 is an embodiment of the position information acquisition unit of the present invention.
The storage unit 152 is an embodiment of the storage means of the present invention.
The display unit 155 is an embodiment of the display means of the present invention.
The geomagnetic sensor 158 is an embodiment of the geomagnetic sensor of the present invention.

  The wireless communication unit 150 performs processing related to wireless communication with the base station 30. For example, the transmission data output from the control unit 160 is subjected to predetermined modulation processing to be converted into a radio signal and transmitted from the antenna. Also, the radio signal received by the antenna is subjected to a predetermined demodulation process to reproduce the received data and output it to the control unit 160.

  The GPS signal receiving unit 151 receives a GPS signal transmitted from the GPS satellite 20, performs signal processing such as amplification, noise removal, and modulation, and acquires information necessary for calculating position information in the GPS server device 401. To do.

  The storage unit 152 stores a program executed by the control unit 160, constant data used in processing of the control unit 160, variable data that needs to be temporarily stored, captured image data, and the like.

The open / close determination unit 153 determines whether the rotation state of the first housing 2 and the second housing 3 by the movable mechanism unit 4 is the open state or the closed state described above.
For example, the open / close determination unit 153 includes a detector such as a switch that detects a closed state in which the first housing 2 and the second housing 3 overlap each other. Determine.

  When an input operation such as pressing a key is performed on the operation key 311 or the camera module tact switch 35 described above, the key input unit 154 generates a signal corresponding to this and outputs it to the control unit 160. .

  The display unit 155 displays an image corresponding to the image data generated by the control unit 160 on the display panel 21.

  The sound processing unit 156 converts the input sound into an electric sound signal by the microphone 312, performs signal processing such as amplification, analog-digital conversion, and encoding, and outputs the sound data of the processing result to the control unit 160. Output. In addition, the audio data input from the control unit 160 is subjected to signal processing such as decoding, digital-analog conversion, and amplification to generate an audio signal, which is converted into audio by the speaker 22.

  The imaging unit 157 captures an incident image in the optical system 34 a described above, generates still image data or moving image image data, and outputs the image data to the control unit 160. Further, according to the control of the control unit 160, the flash lamp is turned on at the time of imaging and is emitted from the light emission window 321.

The geomagnetic sensor 158 detects the geomagnetism used for calculating the azimuth.
For example, as shown in FIG. 6, the geomagnetic sensor 158 detects geomagnetism in three directions orthogonal to each other at a fixed position on the main board 37. That is, the geomagnetism in each axial direction is detected using a predetermined three-axis coordinate system set on the main board 37 as a reference. For the detection of geomagnetism, various methods such as a method using excitation of a coil, a method using the Hall effect, and a method using a magnetoresistive element are used.

  In this embodiment, as an example, the geomagnetic sensor 158 includes an analog-digital converter, which converts a geomagnetic analog signal obtained by the above method into an 8-bit digital signal and outputs it. . That is, the detected values of geomagnetism in three directions are output as integer values from 0 to 255, respectively.

The control unit 160 includes a computer that executes processing based on a program stored in the storage unit 152, and performs various processes related to the overall operation of the mobile phone 100.
For example, as processing related to the function of the telephone, processing for controlling a calling / incoming sequence of the wireless communication unit 150 according to a key input operation in the key input unit 154, and voice data input / output in the voice processing unit 156 Is transmitted / received by the wireless communication unit 150.
As processing related to the data communication function, the wireless communication unit 150 is operated in response to a key input operation in the key input unit 154, communicates with a predetermined mail server device, and exchanges data such as electronic mail. Do.
As processing related to the imaging function, processing for causing the imaging unit 157 to execute imaging processing of a still image or a moving image in response to a key input operation in the key input unit 154, or image processing such as compression encoding on captured image data Processing is performed to store the data in the storage unit 152. When taking a still image, the flash lamp is turned on at an appropriate timing.

  In addition, the control unit 160 calculates the geographical orientation based on the detection value of the geomagnetic sensor 158 as the processing related to the navigation function, and the GPS server device 401 receives the GPS signal information received by the GPS signal receiving unit 151. To acquire the location information of the current location by transmitting to the navigation server device 402, processing to acquire the map information and accuracy information and correction information around the current location, the acquired map information and accuracy information Depending on the process to be displayed on the display unit 155, the process of determining the current location based on the positioning signal from the base station 300 and the calculation result of the direction, the process of calculating the corrected direction based on the correction information, and the calculation result of the direction To perform processing (heading-up display processing) for controlling the orientation of the map on the display screen.

  Further, the control unit 160 rotates the display image of the display unit 155 according to the determination result of the open / close determination unit 153 in order to deal with the fact that the orientation of the display panel 21 with respect to the user differs 180 degrees between the open state and the closed state. The processing to apply is performed.

  Here, the operation of the mobile phone 100 having the above-described configuration will be described focusing on the navigation function related to the present invention.

  First, GPS signal reception processing will be described.

  FIG. 8 is a flowchart illustrating an example of GPS signal reception processing in the mobile phone 100.

  The control unit 160 controls the GPS signal receiving unit 151 at a fixed timing such as an interval of 2 seconds, for example, and scans the GPS signal from the satellite (steps ST102 and ST104). If the GPS signal can be received as a result of the scan, the information is stored in the storage unit 152 (ST106). Such GPS signal scanning and information storage are repeated for all receivable satellites (steps ST108, ST104, ST106). After all the satellites have been scanned, the processing of steps ST104 to ST108 is performed again after waiting for the next GPS signal reception timing. The control unit 160 always executes such GPS signal reception processing, for example, during a power-on period.

  Next, the navigation process will be described.

  FIG. 9 is a flowchart illustrating an example of navigation processing in the mobile phone 100.

When the start of the navigation process is selected, for example, by a key input operation or the like in the key input unit 154 (step ST122), the control unit 100 first obtains the information obtained by the GPS reception process from the radio communication unit 150 from the base station. 300, processing to transmit to the GPS server device 401 via the communication network is performed (step ST124).
When the GPS server device 401 receives GPS information from the mobile phone 100, the GPS server device 401 calculates the position (for example, latitude and longitude information) of the current location of the mobile phone 100 based on the received GPS information, and the calculation result is transmitted to the communication network. To the mobile phone 100 via the base station 300.
The cellular phone 100 receives the position information transmitted from the GPS server device 401 and stores it in the storage unit 152 (step ST126).

Next, the control unit 100 accesses the navigation server device 402 from the wireless communication unit 150 via the base station 300 and the communication network (step ST128), and transmits the acquired position information to the navigation server device 402 (step ST130). .
When the navigation server device 402 receives the location information from the mobile phone 100, the navigation server device 402 searches the database for information on the map around the current location of the mobile phone 100 specified by the location information, and retrieves the searched map information from the communication network to the base station. The data is transmitted to the mobile phone 100 via 300. Further, the accuracy information and the correction information at the current location are read from the database mapped as shown in FIG. 2 and transmitted to the mobile phone 100 together with the map information.
The cellular phone 100 receives the map information, accuracy information, and correction information transmitted from the navigation server device 402 and stores them in the storage unit 152 (step ST132).

FIG. 10 is a diagram illustrating an example of map information transmitted from the navigation server device 402.
In this embodiment, as an example, it is assumed that a unique identification number is assigned to each map information. The navigation server device 402 manages map data for each predetermined size (for example, 1 km square) based on this identification number. When transmitting map information to the mobile phone 100, the navigation server apparatus 402 uses this identification number as the map number. Send it attached to the data. In the example of FIG. 10, the map around the current location is the identification number MP0, and the four maps are the identification numbers MP1 to MP4.

  When such map information is acquired, the control unit 160 generates map image data around the current location based on the acquired map information, and displays the map on the display panel 21 of the display unit 155 (step ST134).

  The area of the map displayed on the display panel 21 is an area (for example, 200 m × 300 m) narrower than the map of 1 km square acquired from the navigation server device 402 as shown in FIG.

The map display method can be selected, for example, from either north-up display (display where the north on the map is on the screen) or heading-up display (display where the traveling direction on the map is on the screen). It is.
When the north-up display is selected by the key operation of the key input unit 154, the control unit 160 fixes the north direction of the map to the upper direction of the display screen and displays it on the display unit 155.

  On the other hand, when the heading-up display is selected by the key operation of the key input unit 154, the control unit 160 performs a process of controlling the orientation of the map on the display screen according to the direction obtained by the direction calculation process described later. . For example, when the traveling direction is a direction A (see FIG. 3) from one end where the microphone 312 of the second housing 3 is disposed to the other end having the connecting portion, the direction of the traveling direction is displayed. The direction of the map on the display screen is controlled so as to go upward.

Note that “above the display screen” described here is a view from the viewpoint of a user who holds the second housing 3 and uses the mobile phone 100, and indicates whether the housing is open or closed. When it is changed, “above the display screen” changes accordingly. That is, when the housing is open, the speaker 22 side of the first housing 2 is above the display screen, and when the housing is open, the connecting portion side of the first housing 2 is above the display screen. .
As will be described later, the control unit 160 performs a process of rotating the image on the display screen in accordance with the open / closed state of the casing, and displays the image in an appropriate direction for the user.

  Further, in step ST134, the control unit 160 causes the display unit 155 to display information related to the accuracy of the geomagnetic detection value based on the accuracy information acquired from the navigation server device 402 together with the map image.

The accuracy information is information indicating whether or not an area where the accuracy of the detection value of the geomagnetic sensor 158 is likely to decrease is included in the area indicated by the map being displayed on the display unit 155. The accuracy-decreasing area is an area with a strong magnetic field that hinders the detection of geomagnetism, and includes an area with a strong magnetic field generated from a building built on the ground or underground, such as a building or a subway. The accuracy information is acquired in advance by, for example, an operation of measuring a magnetic field vector other than geomagnetism in the actual field, and is registered in the navigation server device 402.
The accuracy information indicates, for example, the accuracy-decreasing area included in the area of the map transmitted from the navigation server device 402 together with the accuracy information by coordinates on the map.

The control unit 160 visually displays the accuracy information on the map by, for example, color or shape. That is, the display unit 155 displays a map configured such that the accuracy-decreased area and the other areas are expressed in different colors and forms.
In this case, the map image information including the accuracy-decreasing area may be provided to the mobile phone 100 in advance, for example, by the navigation server device 402, or the control unit 160 of the mobile phone 100 may provide accuracy information and map information. It may be created based on
Alternatively, it may simply be assumed that the inside of a building such as a building or a station premises is an area with reduced accuracy. In this case, the accuracy information is information indicating a region where the building is present as the accuracy-decreasing region, and the control unit 160 of the mobile phone 100 determines the accuracy-decreasing region (that is, the building) based on the accuracy information and the map information. And the other areas are displayed on the display unit 155 in different colors and forms.

  In addition to visually displaying the reduced accuracy area in the map as described above, the control unit 160 determines whether the current location of the mobile phone 100 is included in the reduced accuracy area by using characters, symbols, or the like. You may display on the display part 155. FIG.

  Alternatively, when the compass image representing the azimuth is displayed on the display unit 155, the control unit 160 displays a movement that causes the compass to swing left and right, thereby indicating that the current location is within the accuracy-decreasing region. May be. In addition, the shape, color, and size of the compass image may be changed, or another image indicating that the compass image is in the reduced accuracy area may be displayed.

  Furthermore, if the current location is within the accuracy-decreasing area during the heading-up display, the control unit 160 switches from the heading-up display to the north-up display so that the current location is within the accuracy-decreasing area. May be shown to the user.

  When the display of the map information and the accuracy information is started in this way, the control unit 160 repeats the processing after step ST138 described below until the end of the navigation processing is selected by the key operation of the key input unit 154. (Step ST136).

  First, control unit 160 calculates the position of the current location based on positioning reference signals transmitted from a plurality of (for example, three or more) base stations 300 around mobile phone 100 (step ST138). Then, the presence / absence of movement of the mobile phone 100 is determined from the calculation result of the current location (step ST140). If it is determined that the mobile phone 100 is not moving, the calculation of the current location based on the reference signal from the base station 300 is continued. Perform (ST138).

If it is determined in step ST140 that the mobile phone 100 has moved, the control unit 160 determines whether or not the destination location is in the area of the edge of the currently acquired map (step ST142). For example, when a part of the map to be displayed on the display unit 155 is not included in the currently acquired map and is included in a map adjacent thereto, the current location is in the area at the end of the map. judge.
If it is determined that the current location is in the end region, the control unit 160 requests the navigation server device 146 for a map adjacent to the end region (step ST146). For example, the navigation server device 146 is transmitted to the navigation server device 146 with the identification number of the currently acquired map and the information indicating which of the east, west, north, and north directions is adjacent to the map.
The navigation server device 146 detects a map corresponding to these pieces of information sent from the mobile phone 100 from the database, and transmits the map to the mobile phone 100. Further, new accuracy information and correction information are transmitted to the mobile phone 100 in association with the map information.
The cellular phone 100 receives the map information, accuracy information, and correction information transmitted from the navigation server device 402, stores them in the storage unit 152 (step ST132), and causes the display unit 155 to display the map information and accuracy information ( Step ST134). Thereafter, the processes after step ST138 are repeated.
If it is determined that the current location is not in the end region, the control unit 160 performs a process of moving the map display region so that the current location is the center of the map, for example, according to the calculated current location, and thereafter, The processes after ST138 are repeated.

  Next, display image rotation processing according to the open / closed state of the housing will be described.

  FIG. 11 is a flowchart illustrating an example of display image rotation processing in the mobile phone 100.

Control unit 160 constantly monitors the open / closed state determined by open / close determining unit 153 while the power is on (step ST162). When the open / close determination unit 153 determines that it is not in the closed state (that is, in the open state), an image is displayed on the display panel 21 in a direction in which the speaker 22 side of the first housing 2 is above the image (step ST166). ).
If the display in the open state is a normal display, when the open / close determining unit 153 determines the closed state, the control unit 160 rotates the image in the normal display by 180 degrees and displays the image on the display panel 21 (step ST164). That is, an image is displayed on the display panel 21 in a direction in which the connecting portion side in the first housing 2 is above the image.
By such display image rotation processing, an image can be displayed on the display unit 155 in a direction that is always easy for the user to see regardless of whether the housing is open or closed.

Next, the azimuth calculation processing will be described.
Here, first, the outline of the direction calculation method will be described with reference to FIG. 12, and then the direction calculation processing in the control unit 160 will be described with reference to FIG.

FIG. 12 is a diagram for explaining a method of calculating the azimuth angle.
In FIG. 12, a rectangular coordinate system having coordinate axes Hx, Hy, Hz is a reference coordinate system set on the ground plane. That is, the coordinate axes Hx and Hy are coordinate axes parallel to the ground plane, and each face a predetermined direction. The coordinate axis Hz is a coordinate axis that faces in a direction perpendicular to the ground plane.
The azimuth angle θ is an angle formed by an image Zxy obtained by orthogonally projecting a vector in the reference direction (for example, direction A in FIG. 3) of the geomagnetic detection set on the main substrate 37 of the second housing 3 to the ground plane and the coordinate axis Hx. It is. The inclination angle φ is an angle formed by the image Zxy and a vector in the reference direction A. Further, the twist angle η is an angle obtained by rotating the mobile phone 100 around the rotation axis about the vector in the reference direction A.
When the azimuth angle θ, the inclination angle φ, and the twist angle η are all zero, the geomagnetic detection coordinate system set on the main board 37 of the second housing 3 has coordinate axes Hx, Hy, and Hz shown in FIG. Match the coordinate system.

  Here, when the detected value of geomagnetism corresponding to the coordinate axis Hx is α, the detected value of geomagnetism corresponding to the coordinate axis Hy is β, and the detected value of geomagnetism corresponding to the coordinate axis Hz is γ, the tangent of the azimuth angle θ shown in FIG. tan θ is expressed by the following equation.

(Equation 1)
tan θ = β / (γ · sin φ−α · cos φ) (1)

However, in the formula (1), the twist angle η is zero.
The control unit 160 calculates the azimuth angle from the detected values of the geomagnetism in the three directions obtained from the geomagnetic sensor 158 using the relationship shown in the equation (1), for example.

The control unit 160 also takes into account the inclination angle of the display panel 21 with respect to the ground plane when calculating the above-described azimuth.
A general user can view an image on the display panel 21 with an easy posture when the display panel 21 is tilted at an angle of about 45 degrees, for example. Therefore, the control unit 160 calculates the azimuth by Expression (1) using the inclination angle φ when the inclination angle of the display panel 21 with respect to the ground plane is 45 degrees, for example.

In addition, when the inclination angle of the geomagnetic sensor 158 with respect to the ground plane is different between the open state and the closed state, the control unit 160 may calculate the azimuth angle of each state in consideration of the difference in the inclination angle.
For example, the first housing 2 and the second housing 3 overlap each other substantially in parallel in the closed state, whereas the first housing 2 and the second housing 3 are relatively inclined in the open state (for example, “ It is assumed that the two housings are connected so as to incline in the shape of "". In this case, if the user tries to keep the direction of the line of sight with respect to the display panel 21 constant in both operation styles, the inclination of the second housing 3 with respect to the ground plane differs between the open state and the closed state. That the inclination of the second housing 3 is different means that the inclination of the reference direction A with respect to the ground plane is different in the open and closed states. Therefore, the control unit 160 calculates the azimuth using the predetermined inclination angle φ according to the determination result of the open / close determination unit 153. The tilt angle φ is an angle set so that the tilt angle of the display panel 21 with respect to the ground plane is constant at, for example, 45 degrees in both the open state and the closed state.

  The information on the tilt angle is stored in advance in the storage unit 152 as a data table, for example. When the azimuth is detected, the control unit 160 reads the tilt angle information associated with the determination result of the open / close determination unit 153 from the data table, and calculates the azimuth based on the information.

  FIG. 13 is a flowchart illustrating an example of the orientation calculation process in the mobile phone 100.

  When the start of the navigation process is selected by a key input operation or the like in the key input unit 154 (step ST202), the control unit 160 determines that the current location of the mobile phone 100 is reduced based on the accuracy information acquired from the navigation server device 402. It is determined whether or not the area is included (step ST204).

The accuracy information acquired from the navigation server device 402 includes, for example, information on coordinates of a reduced accuracy area on the map (information on a coordinate range indicating an area on the map, etc.) sent from the navigation server device 402.
In this case, the control unit 160 determines whether or not the current location of the mobile phone 100 is included in the accuracy-reduced area from the coordinate information included in the accuracy information.

  If it is determined that the current location of the mobile phone 100 is included in the accuracy-decreased area, the control unit 160 sets the magnetic field state at the current location in a state where the azimuth can be calculated by the correction process based on the correction information acquired from the navigation server device 402. It is determined whether or not there is (step ST206), and when it is determined that the azimuth can be calculated, the azimuth is calculated using the correction information.

The correction information is information for correcting the azimuth according to the state of the magnetic field at the current location of the mobile phone 100. For example, flag information indicating whether or not the azimuth can be calculated at the current location, and the correction of the azimuth. Value.
In step ST206, the control unit 160 determines whether or not the azimuth can be calculated based on the flag information. If it is determined that calculation is possible, in step ST208, the corrected orientation is calculated based on the correction value.

  When calculating the corrected azimuth, for example, the control unit 160 adds a positive or negative correction value acquired as correction information to the result of calculating the azimuth based on Expression (1). This correction value is acquired in advance, for example, by an operation of measuring a magnetic field vector other than geomagnetism in the actual field, and registered in the navigation server device 402.

  The correction information may represent the same content as the flag information using the correction value without having the flag information as described above. For example, when the correction value is larger (or smaller) than a predetermined threshold value, it may represent that the azimuth cannot be calculated at the current location.

If it is determined in step ST204 that the current location is not within the accuracy-decreased area, the control unit 160 calculates the azimuth based on, for example, equation (1) without using the correction value of the correction information described above.
If it is determined in step ST206 that the calculation of the current position cannot be calculated, the control unit 160 proceeds to step ST212 described below without calculating the direction.

  After calculating the azimuth in step ST208 or ST201, or after passing the calculation of the azimuth in step ST206, the control unit 160 checks whether the end of the navigation process is selected by operating the key input unit 154 or the like (step (ST212) When it is confirmed that the process continues, the processes of steps ST204 to ST210 described above are repeated.

As described above, according to the present embodiment, when the orientation information and the map are displayed on the display unit 155, the accuracy of the detection value of the geomagnetic sensor 158 is within the area indicated by the displayed map. Accuracy information indicating whether or not an accuracy-decreasing area that is likely to be reduced is included is acquired from the navigation server device 402 and displayed on the display unit 155.
As a result, the user can correctly grasp whether or not the accuracy of the currently displayed azimuth information is low. For example, if the accuracy of orientation information is low, the orientation can be determined by another method, such as comparing the information displayed on the map with the surrounding landscape without referring to the orientation displayed on the screen. Since it is clear for the user that a register should be obtained, the ease of use of the navigation function can be improved.

Further, according to the present embodiment, when the direction information and the map are displayed on the display unit 155, the correction information of the direction according to the state of the magnetic field at the current location of the mobile phone 100 is acquired from the navigation server device 402. Then, the corrected orientation is calculated based on the correction information.
Therefore, it is possible to accurately correct an azimuth error caused by a magnetic field generated by a building or the like, which is a problem during navigation in a city. Thereby, even in a harsh environment for geomagnetism detection where buildings are densely packed, it becomes possible to accurately display direction information to the user, and the ease of use of the navigation function can be further improved.

<Second Embodiment>
Next, a second embodiment of the present invention will be described.
In the second embodiment, the direction information is displayed and the direction is corrected based on the accuracy information and the correction information reflecting the state of the magnetic field that changes according to the time zone.

Here, the navigation system according to the second embodiment has the same configuration as FIG. 1, and the mobile phone according to the second embodiment has the same configuration as the mobile phone 100 shown in FIGS. And
Below, the navigation process of this embodiment different from 1st Embodiment is demonstrated.

14 and 15 are flowcharts illustrating an example of navigation processing of the mobile phone 100 according to the second embodiment.
The same reference numerals in FIG. 9, FIG. 14 and FIG. The difference between the two is that step ST132 shown in FIG. 9 is replaced with step ST148 in FIG. 14 and step ST150 is added in FIG.

The navigation server device 402 has, for example, the above-described accuracy information map and correction information map for a plurality of different time zones. When a request for map information, accuracy information, and correction information is received from the mobile phone 100, accuracy information and correction information are obtained from the accuracy information map and the correction information map accuracy information corresponding to the current time measured by a time measurement process based on a GPS signal or the like. Is transmitted to the mobile phone 100 together with the map information.
The mobile phone 100 receives the map information around the current location and the accuracy information and correction information of the current time transmitted from the navigation server device 402, stores them in the storage unit 152 (step ST148), and after step ST134 described above. Process.

If it is determined in step ST140 that the terminal has not moved, or if it is determined in step ST142 that the current location is not in the edge region of the map and the display area is moved in step ST114, the control unit 160 performs navigation. It is determined whether or not new accuracy information and correction information should be acquired from the server device 402 (step ST150).
This process is a process for acquiring appropriate accuracy information and correction information according to the time zone from the navigation server device 402. For example, it is determined that the accuracy information and the correction information should be acquired every time a predetermined time elapses. I do.
If it is determined that new accuracy information and correction information should be acquired, the control unit 160 moves the process to step ST148, acquires accuracy information and correction information of the current time from the navigation server device 402, and after step ST134. Repeat the process.
When it is determined that it is not necessary to acquire new accuracy information and correction information, the control unit 160 moves the process to step ST136, confirms whether or not the end of the navigation process is selected, and continues the navigation process. If so, the processes in and after step ST138 are repeated.

  As described above, according to the present embodiment, the accuracy-reduced area is displayed using the accuracy information that reflects the state of the different magnetic field depending on the time zone even at the same point or the same area. , It is possible to inform the user of the accuracy of more accurate azimuth. For example, it is possible to inform the user of more accurate azimuth accuracy including the vicinity of the railway in the commuting time zone and the time zone where it is not, and the state of the magnetic field around the factory in the operation time zone and the time zone where it is not.

  In addition, since the azimuth correction is performed using the correction information reflecting the state of the magnetic field that varies depending on the time zone, more accurate azimuth information can be provided to the user.

<Third Embodiment>
Next, a third embodiment of the present invention will be described.
In the third embodiment, accuracy information and correction information are stored in storage means on the terminal side.

Here, it is assumed that the mobile phone according to the third embodiment has the same configuration as the mobile phone 100 shown in FIGS.
However, the mobile phone according to the third embodiment does not access the GPS server device 401 or the navigation server device 402 shown in FIG. 1, and stores information (map) obtained by these server devices in the storage unit 152 in its own terminal. Information, accuracy information, correction information).
Below, the navigation process of this embodiment different from 1st and 2nd embodiment is demonstrated.

  FIG. 16 is a flowchart illustrating an example of navigation processing of the mobile phone 100 according to the third embodiment.

  When the start of the navigation process is selected, for example, by a key input operation or the like in the key input unit 154 (step ST302), the control unit 100 first determines the mobile phone based on the information obtained by the GPS reception process similar to FIG. The position of the current location of 100 (for example, latitude and longitude information) is calculated (step ST304).

Next, the control unit 100 acquires information on a map around the current location of the mobile phone 100 specified by the position information calculated in step ST304 from the database in the storage unit 152.
Further, the control unit 100 performs a time measurement process for measuring the current time based on the GPS signal and the like, and based on the accuracy information map and the correction information map in the storage unit 152 corresponding to the current time obtained by the time measurement process, the current time Accuracy information and correction information are acquired at step ST306.

  When the map information is acquired from the storage unit 152, the control unit 160 generates map image data around the current location based on the acquired map information, and displays the map on the display panel 21 of the display unit 155 (step ST308). The map display method can be selected from display methods such as north-up display and heading-up display.

  Further, in step ST308, the control unit 160 causes the display unit 155 to display accuracy information acquired from the storage unit 152 together with the map image. For example, a map configured such that the accuracy-reduced area and other areas are represented in different colors and forms may be displayed on the display unit 155, and the current location of the mobile phone 100 is included in the accuracy-reduced area. It may be displayed on the display unit 155 by characters or symbols.

  When the display of the map information and the accuracy information is started in this way, the control unit 160 repeats the processes after step ST312 described below until the end of the navigation process is selected by the key operation of the key input unit 154. (Step ST310).

First, control section 160 calculates the position of the current location based on positioning reference signals transmitted from a plurality of base stations 300 around mobile phone 100 (step ST312).
Then, the presence / absence of movement of the mobile phone 100 is determined from the calculation result of the current location (step ST314), and if it is determined that the mobile phone 100 has moved, the destination location is the area of the edge of the currently acquired map. Is further determined (step ST142). For example, when a part of the map to be displayed on the display unit 155 is not included in the currently acquired map and is included in a map adjacent thereto, the current location is in the area at the end of the map. judge.
When it is determined that the current location is in the end area, the control unit 160 acquires map information adjacent to the end area, and accuracy information and correction information corresponding to the map area from the storage unit 152 (step ST306). The acquired map information and accuracy information are displayed on the display unit 155 (step ST308). Thereafter, the processes after step ST312 are repeated.
If it is determined that the current location is not in the end region, the control unit 160 performs a process of moving the map display region so that the current location is at the center of the map, for example, according to the calculated current location (step ST318). The process moves to step ST320 described later.

If it is determined in step ST314 that the terminal is not moving, or if it is determined in step ST316 that the current location is not in the edge region of the map and the display area is moved in step ST318, the control unit 160 stores the storage unit 152. From this, it is determined whether or not new accuracy information and correction information should be acquired (step ST320).
This process is a process for acquiring appropriate accuracy information and correction information according to the time zone from the storage unit 152. For example, it is determined that the accuracy information and the correction information should be acquired every time a predetermined time elapses. Do.
When it is determined that new accuracy information and correction information should be acquired, the control unit 160 moves the process to step ST306, acquires accuracy information and correction information of the current time from the storage unit 152, and performs steps after step ST308. Repeat the process.
When it is determined that it is not necessary to acquire new accuracy information and correction information, the control unit 160 moves the process to step ST310, confirms whether or not the end of the navigation process is selected, and continues the navigation process. If so, the processes in and after step ST312 are repeated.

  As described above, even when accuracy information and correction information are stored in the storage unit on the terminal side, as in the first and second embodiments, accurate azimuth information and accuracy information are stored. Can be provided to the user.

<Fourth Embodiment>
Next, a fourth embodiment of the present invention will be described.
In the fourth embodiment, the server device is notified of the abnormality information of the geomagnetic detection value generated at the terminal, and the accuracy information of the server device is updated according to the notification information.

Here, the navigation system according to the fourth embodiment has the same configuration as in FIG. 1, and the mobile phone according to the fourth embodiment has the same configuration as the mobile phone 100 shown in FIGS. And
Below, the geomagnetic detection value abnormality notification process and the accuracy information update process of this embodiment, which are processes added to the first or second embodiment, will be described.

  FIG. 17 is a flowchart illustrating an example of a geomagnetic detection value abnormality notification process executed in the mobile phone 100 according to the present embodiment.

When the start of the navigation process is selected by a key input operation or the like in the key input unit 154 (step ST402), the control unit 160 checks whether the detection value of the geomagnetic sensor 158 is in a predetermined abnormal state (step ST404).
For example, an overflow has occurred in any one of the 8-bit geomagnetic detection values represented by integer values from “0” to “255” (the detection value is the minimum value “0” or the maximum value “255”). Or a state in which any one of the detected geomagnetism values is out of a predetermined normal range is detected as an abnormal state.

When detecting such an abnormal state of the geomagnetic detection value, control unit 160 measures the time during which the abnormal state continues from the time of the detection (step ST406). When the abnormal state ends within a predetermined time (for example, 5 seconds), the control unit 160 determines that an error has occurred in the geomagnetic detection value due to the external magnetic field (step ST408), and the position information of the current location is obtained from the navigation server device 402. (Step ST410).
For example, when the mobile phone 100 becomes magnetized by bringing the mobile phone 100 close to an object that generates a strong magnetic field such as a speaker, the detection value of the geomagnetic sensor 158 is a state in which an error (offset error) is constantly generated. become. Such an offset error can be easily calculated, for example, by detecting geomagnetism while rotating the mobile phone 100 and obtaining a vector locus of a detected value of the geomagnetic sensor corresponding to the rotation. The control unit 160 executes a process of calculating and correcting the offset error at regular intervals, for example, to suppress a decrease in accuracy of the calculated direction value due to magnetization of the mobile phone 100.
On the other hand, abnormalities in the detected value of the geomagnetism caused by an external magnetic field do not often continue constantly like an offset error, and are usually transient in many cases. For example, when the geomagnetic sensor 158 detects a magnetic field generated by a passing car or train, the detected value temporarily becomes an abnormal state (overflow state or the like). In addition, for example, when the user navigates while walking, the detected value of the geomagnetic sensor 158 temporarily becomes abnormal when passing a building that generates a magnetic field.
Such an error in the detected value of the geomagnetism due to the external magnetic field cannot be corrected by a method of rotating the mobile phone 100 like an offset error, leading to a decrease in the accuracy of the calculated direction value.
Therefore, when an abnormality such as an overflow occurs temporarily in the geomagnetic detection value, the control unit 160 determines that an abnormality in the geomagnetic detection value due to the external magnetic field has occurred, and notifies the navigation server device 402 of the position where this abnormality has occurred. To do.

After notifying the server device 402 of the abnormality of the detected geomagnetism value, the control unit 160 checks whether or not the end of the navigation process is selected (step ST412), and if it is confirmed that the process will continue, the above-described step ST404 is performed. Repeat the process of ~ ST410.
In addition, when the abnormal state of the geomagnetic detection value is not detected in step ST404, or when it is determined in step ST408 that the abnormal state of the geomagnetic detection value has continued for a predetermined time or more, after confirming the continuation of the navigation process, The processes in steps ST404 to ST410 are repeated.

FIG. 18 is a flowchart illustrating an example of accuracy information update processing in the navigation server device 402 according to this embodiment.
The navigation server device 402 receives a notification of an abnormality occurrence point of the geomagnetic detection value from the mobile phone 100 (step ST502), and updates the accuracy information in the accuracy information map based on the received notification (step ST504). For example, when notification of abnormal geomagnetic detection values is received from a predetermined number of mobile phones within a predetermined time within a predetermined size range (a range of several meters square, etc.), the accuracy information is set with the range where the abnormality occurrence frequency is high as the accuracy decreasing area. Register on the map. Such a registration process is performed on, for example, an accuracy information map determined for each predetermined time period.

As described above, according to the present embodiment, when the detected value of the geomagnetic sensor 158 is in a predetermined abnormal state when the direction information is displayed on the display unit 155, the point where the abnormal state has occurred. Is provided from the mobile phone 100 to the navigation server device 402. In the navigation server device 402, based on the positional information of the abnormal state occurrence point of the geomagnetic detection value provided from the mobile phone 100, the accuracy information held in advance for the point is updated.
Therefore, the situation of the magnetic field in the city that changes every moment due to the appearance of a new building or the like can be accurately reflected in the accuracy information, so that more accurate azimuth accuracy information can be provided to the user.
Further, by checking the update state of the accuracy information in the navigation server device 402, it is possible to easily grasp the state of the magnetic field change in the city, so that the actual magnetic field measurement for obtaining accuracy information and correction information is performed. In this case, the work can be reduced because the work can be performed in an area where the magnetic field change is significant.

  Although several embodiments of the present invention have been described so far, the present invention is not limited to the above-described embodiments, and includes various variations.

  In the above-described embodiment, an example in which geomagnetism in three directions is detected by the geomagnetic sensor 158 has been described.

  In the azimuth calculation process shown in FIG. 13, correction based on the correction information is performed only in the accuracy-decreased area. good.

In the above-described embodiment, map rotation processing (for example, heading-up display) is performed on the mobile phone 100. However, the present invention is not limited to this, and for example, the mobile phone 100 indicates the map display direction with respect to the navigation server device 402. The map information may be requested and the navigation server device 402 may generate map information in a direction corresponding to the request from the mobile phone 100 and provide the map information to the mobile phone 100.
That is, the control unit 160 performs processing for acquiring map image information corresponding to the orientation calculated based on the detected geomagnetism value from the navigation server device 402 and displaying the map information on the display unit 155. When entering the lowered area, map information of a preset orientation may be acquired from the navigation server device 402 and displayed on the display unit 155 regardless of the calculated orientation.

In the above-described embodiment, an example in which the processing of the control unit 160 is executed based on a program by a computer has been described. However, at least a part of these processing can be executed using hardware without using a computer. It is.
Conversely, at least a part of processing in units other than the control unit 160 may be executed by the computer of the control unit 160.

  In the above-described embodiment, a mobile phone in which the first housing and the second housing are rotatably connected is shown as an example, but the present invention is not limited to this. For example, two housings may be connected so as to be foldable or slidable, or a structure including a display unit and a key operation unit in one housing may be employed.

  Further, the mobile communication terminal of the present invention is not limited to a mobile phone. For example, the present invention can be widely applied to portable terminal devices having communication functions such as PDAs.

  In the above description, the present invention is divided into the first to fourth embodiments to simplify the description, but the present invention is not limited to this. That is, this invention includes what has each form independently, and what combined these forms arbitrarily.

  DESCRIPTION OF SYMBOLS 2 ... 1st housing | casing, 3 ... 2nd housing | casing, 4 ... Movable mechanism part, 21 ... Display panel, 100 ... Mobile phone, 200 ... GPS satellite, 300 ... Base station, 401 ... GPS server apparatus, 402 ... Navigation Server device 150... Wireless communication unit 151... GPS signal receiving unit 152. Storage unit 153 Open / close determination unit 154 Key input unit 155 Display unit 156 Audio processing unit 157 Imaging unit 158 ... Geomagnetic sensor, 159 ... Memory card part, 160 ... Control part.

Claims (8)

Wireless communication means;
A geomagnetic sensor for detecting geomagnetism;
Position information acquisition means for acquiring information related to the geographical position of the current location;
Display means;
The geographical direction is calculated based on the detection value of the geomagnetic sensor, and the calculated direction information and the map around the current location specified based on the position information acquired by the position information acquisition unit are displayed. Control means to be displayed on the means;
A mobile communication terminal having
The control means performs a time measurement process for measuring the current time, and the accuracy-decreased area where the accuracy of the detection value of the geomagnetic sensor is likely to decrease at the current time in the area indicated by the map displayed on the display means. A mobile communication terminal, wherein accuracy information indicating whether or not is included is acquired from a predetermined information provider via the wireless communication unit, and the acquired accuracy information is displayed on the display unit. A geomagnetic sensor for detecting geomagnetism;
Position information acquisition means for acquiring information related to the geographical position of the current location;
Display means;
The geographical direction is calculated based on the detection value of the geomagnetic sensor, and the calculated direction information and the map around the current location specified based on the position information acquired by the position information acquisition unit are displayed. Control means to be displayed on the means;
A mobile communication terminal having
Having storage means for storing information on the accuracy-decreasing area where the accuracy of the detection value of the geomagnetic sensor according to the time is likely to decrease;
The control means performs a time measurement process for measuring the current time, and whether or not the reduced accuracy area is included in the area indicated by the map displayed on the display means at the current time obtained by the time measurement process. The mobile communication terminal is characterized in that accuracy information indicating is displayed on the display means. The control means controls the orientation of the map according to the azimuth information when displaying the azimuth information and the map on the display means. The portable communication terminal as described. The said control means fixes the said map to a predetermined | prescribed direction, and displays it on the said display means, when the present location specified based on the said positional information is contained in the said accuracy fall area. The mobile communication terminal according to any one of claims 3 to 3. The control means causes the display means to display information indicating whether or not the current location specified based on the position information is included in the reduced accuracy area. The mobile communication terminal according to claim 1. When the detected value of the geomagnetic sensor is in a predetermined abnormal state while displaying the azimuth information on the display unit, the control unit uses the position information acquisition unit at a point where the abnormal state occurs. The mobile communication terminal according to claim 1, wherein the acquired position information is transmitted to the predetermined information provider by the wireless communication means. Wireless communication means, geomagnetic sensor for detecting geomagnetism, position information acquisition means for acquiring information related to the geographical position of the current location, information on the geographical orientation calculated based on the detection value of the geomagnetic sensor, An information display method for a mobile communication terminal for displaying information on a mobile communication terminal having display means for displaying a map around a current location specified based on position information acquired by the position information acquisition means ,
When the information on the azimuth and the map are displayed on the display means, the accuracy of the detection value of the geomagnetic sensor is reduced at the current time in the area indicated by the map displayed on the display means. A first step of acquiring accuracy information indicating whether or not easy-to-decrease areas are included from a predetermined information provider via the wireless communication means;
And a second step of displaying the accuracy information acquired in the first step on the display means. Wireless communication means, geomagnetic sensor for detecting geomagnetism, position information acquisition means for acquiring information related to the geographical position of the current location, information on the geographical orientation calculated based on the detection value of the geomagnetic sensor, The display means for displaying a map around the current location specified based on the position information acquired by the position information acquisition means, and the accuracy-reduced area where the accuracy of the detection value of the geomagnetic sensor corresponding to the time is likely to decrease. An information display method for a mobile communication terminal for displaying information in a mobile communication terminal having storage means for storing information,
A first step of measuring the current time;
A second display for displaying accuracy information indicating whether or not the reduced accuracy area is included in the area indicated by the map displayed on the display means at the current time obtained by the first step; And the process of
An information display method for a mobile communication terminal, comprising:

Images